/*  mbed Microcontroller Library
    Copyright (c) 2015 ARM Limited

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
*/
#ifndef MBED_TICKER_API_H
#define MBED_TICKER_API_H

#include "device.h"

typedef uint32_t timestamp_t;

/** Ticker's event structure
*/
typedef struct ticker_event_s {
    timestamp_t            timestamp; /**< Event's timestamp */
    uint32_t               id;        /**< TimerEvent object */
    struct ticker_event_s* next;      /**< Next event in the queue */
} ticker_event_t;

typedef void (*ticker_event_handler)(uint32_t id);

/** Ticker's interface structure - required API for a ticker
*/
typedef struct {
    void (*init)(void);                           /**< Init function */
    uint32_t (*read)(void);                       /**< Read function */
    void (*disable_interrupt)(void);              /**< Disable interrupt function */
    void (*clear_interrupt)(void);                /**< Clear interrupt function */
    void (*set_interrupt)(timestamp_t timestamp); /**< Set interrupt function */
} ticker_interface_t;

/** Tickers events queue structure
*/
typedef struct {
    ticker_event_handler event_handler; /**< Event handler */
    ticker_event_t* head;               /**< A pointer to head */
} ticker_event_queue_t;

/** Tickers data structure
*/
typedef struct {
    const ticker_interface_t* interface; /**< Ticker's interface */
    ticker_event_queue_t* queue;         /**< Ticker's events queue */
} ticker_data_t;

#ifdef __cplusplus
extern "C" {
#endif

/** Initialize a ticker and sets the event handler

    @param data    The ticker's data
    @param handler A handler to be set
*/
void ticker_set_handler(const ticker_data_t* const data, ticker_event_handler handler);

/** Irq handler which goes through the events to trigger events in the past.

    @param data    The ticker's data
*/
void ticker_irq_handler(const ticker_data_t* const data);

/** Remove an event from the queue

    @param data The ticker's data
    @param obj  The event's queue to be removed
*/
void ticker_remove_event(const ticker_data_t* const data, ticker_event_t* obj);

/** Insert an event from the queue

    @param data      The ticker's data
    @param obj       The event's queue to be removed
    @param timestamp The event's timestamp
    @param id        The event object
*/
void ticker_insert_event(const ticker_data_t* const data, ticker_event_t* obj, timestamp_t timestamp, uint32_t id);

/** Read the current ticker's timestamp

    @param data The ticker's data
    @return The current timestamp
*/
timestamp_t ticker_read(const ticker_data_t* const data);

/** Read the next event's timestamp

    @param data The ticker's data
    @return 1 if timestamp is pending event, 0 if there's no event pending
*/
int ticker_get_next_timestamp(const ticker_data_t* const data, timestamp_t* timestamp);

#ifdef __cplusplus
}
#endif

#endif
